Liquid crystal display device and method of manufacturing the same

The present invention discloses a method of manufacturing a liquid crystal display device, including: providing a substrate; depositing sequentially a first metal layer and a first insulating layer on the substrate; patterning the first metal layer and the first insulating layer using a first mask to form a gate line and a first gate insulating layer; depositing sequentially a second gate insulating layer, a pure semiconductor layer, a doped semiconductor layer and a second metal layer over the whole substrate; patterning the second metal layer using a second mask to form a data line, source and drain electrodes, a capacitor electrode, the capacitor electrode overlapping a portion of the gate line; etching the doped semiconductor layer between the source and drain electrodes to form a channel region; depositing a third insulating layer over the whole substrate; patterning the third insulating layer using a third mask to form a passivation film, the passivation film having a smaller width than the data line and covering the source and drain electrodes and exposing a portion of the drain electrode and the capacitor electrode; depositing a transparent conductive material layer over the whole substrate; and patterning the transparent conductive material layer using a fourth mask to pixel electrode, the pixel electrode contacting the drain electrode.